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Alternators & voltage regulators - NOT Haflinger
Posted: Tue Sep 23, 2014 3:25 pm
by Julian B
I hope the mods will forgive me, but I have a non-Haflinger query which some of the more technically minded might be able to help me with.
I have a Swiss-made Aebi TT60 tractor (1997) with a large flail on the front, which I use for scrub clearance on (comparatively) very steep slopes in the UK. It is highly dependent on electric solenoids / relays (???) to activate the hydraulic rams etc. Recently the hydraulic rams have been stopping working after about 30-60 minutes use of the machine, and the battery has no charge. (I always keep the Aebi on a trickle charger when in the barn, so it always starts out fully charged.) The battery has been checked, and it is not broken.
I was advised to change the alternator, as it was obviously not producing enough power to charge the battery / power the solenoids - as evidenced by a multimeter. The new one I fitted didn't solve my problems so I sent it back and they confirmed that it had a duff voltage regulator in it; the replacement should arrive tomorrow.
Question: Could anything on the Aebi have caused the new alternator's voltage regulator to die, or would it have been dead before I fitted it? Can I test anything on the Aebi before I re-install the new alternator to make sure I don't kill the new one?
TIA
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Tue Sep 23, 2014 6:51 pm
by heinkeljb
Julian,
If you had connected it up with the battery still connected, that could have damaged the voltage regulator on replacement alternator. Is the replacement alternator you are getting tomorrow a "direct" replacement? i.e. is it from the manufacturer or for the dealer or just from a shop that sells alternators?
Don't run the alternator without the wiring all connected up as that can damage the regulator pack on alternator.
It is far more likely that it was already faulty as I can't see you doing either of the above things - connecting with battery still connected or running it without any wires.
John
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Tue Sep 23, 2014 7:16 pm
by Julian B
Hi John, thanks for that.
I would have certainly connected the battery as a final step of the installation this time - of that I am 100% sure. In fact I am sure that everything was connected within the Aebi prior to connecting the battery.
In the past with the old alternator, when the battery had been flattened and I needed to use a spare to re-start the Aebi in the field, I would have disconnected the spare with the engine running so that I could re-connect the proper battery, but other than that all wiring / connections would have been in place & correct. (The spare battery that I have won't physically fit in the battery bay properly, so I have to remove it in order to drive the Aebi back to the yard). Might this have been the cause?
I bought the replacement alternator from [edit - link removed in case they do a google search
![Wink ;)](./images/smilies/icon_e_wink.gif)
] - having found that the specific (Bosch?) model number on their website first. I returned the old core as part of the deal. Other than the duff voltage regulator I have been impressed with their service.
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Tue Sep 23, 2014 7:23 pm
by StuartR
An alternator must always be connected when energised and running. If not then the diodes will get a voltage spike that will destroy them and can also damage the regulator. Do not disconnect the battery at all or the earth/live connections when running or when the alternator is energised.
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Tue Sep 23, 2014 7:29 pm
by Julian B
StuartR wrote:Do not disconnect the battery at all or the earth/live connections when running or when the alternator is energised.
Hmmmm.
![Embarrassed :oops:](./images/smilies/icon_redface.gif)
Perhaps that is what killed the voltage regulator on the replacement alternator. But this doesn't explain why the battery is being depleted and needs re-charging externally. I'll fit the new alternator and make sure I don't disconnect the battery with the engine running again - even if it means buying a second battery that does fit in the battery tray properly.
Thanks for the info!
![Embarrassed :oops:](./images/smilies/icon_redface.gif)
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Tue Sep 23, 2014 7:46 pm
by tpond
As a matter of course, I would double check that all of the earth connections are clean and tight.
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Wed Sep 24, 2014 2:44 am
by AustHaflinger
Yes - Stuart is correct - an alternator MUST always be connected to a battery, even if it is a dud battery when running.
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Wed Sep 24, 2014 3:23 am
by RPower
You could have sulfated battery plates if it is on a charger, even a trickle charger, all the time. Incomplete and improper charging can surely wreak havok on a battery. I see it quite often at work when customers start driving their "summer" vehicles after having them on a "trickle charger" all winter. I've seen alternators fail as well due to poor battery condition. Just a guess, but something to look into. Here's a link to some general info on this subject.
http://support.rollsbattery.com/support ... 64-battery
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Wed Sep 24, 2014 3:44 am
by Julian B
Thanks for that; I use one of these
www.accumate.co.uk on several classic cars / under used machines (I have 12 vehicles with only 2 being used frequently!) and I have always understood that they are "intelligent" and do a cyclical charge to prevent improper charging - but I might be wrong. I did take the battery to a garage and they tested it and said that it was fine / holding its charge OK. But perhaps a new battery would be a sensible investment anyway.
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Wed Sep 24, 2014 4:47 am
by RPower
Good old fashioned Load Tests usually do a great job of flushing out bad batteries. Good luck sir!
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Wed Sep 24, 2014 7:28 am
by heinkeljb
Julian,
I have a battery drop tester (tests battery by putting a heavy load on it and measuring the voltage) if you want to use it.
Buy a pair of heavy duty jump leads and put the spare battery on the ground next to the vehicle. Connect up the jump leads with original battery still in place in the battery box. I.e. run the two batteries in parallel. When engine has started, you can disconnect the jump leads without having to disconnect the original battery.
As mentioned above - Never disconnect / reconnect the battery from an alternator powered system when the alternator is turning - It WILL kill the voltage regulator in the alternator when you connect it back up.
John
Re: Alternators & voltage regulators - NOT Haflinger
Posted: Wed Sep 24, 2014 9:45 am
by Julian B
John, I do have a battery drop tester, and although it told me the battery was OK I wanted a "proper" garage to confirm that.
http://tinyurl.com/mgjxka3
A few years ago a friend made some mega jump leads for me, with some VERY thick arc welding cables, so am sure that they are up to the job - but I'll use your suggestion next time!
Thanks all!